Mineral oil composition



Patented Apr. 29, 1947 2,419,588 MINERAL OIL COMPOSITION Ferdinand P. Otto, Woodbury, and Ronald E.

Meyer, Gloucester, N. J., asaignors to Socony- Vacnum Oil Company, Incorporated, a corporation of New York 19 Claims.

This invention has to do with mineral oil compositions and more particularly has to do with viscous mineral oil fractions of the type used for lubricants, dielectrics and the like, which have been improved in one or more of their various properties by the addition thereto of an oil improving agent.

It is well recognized by those familiar with the art that viscous mineral oil fractions tend to deteriorate when used as lubricants in present day internal combustion engines. In such use these oil fractions develop substantial quantities of carbonaceous deposits which accumulate as sludge or carbon deposits impairing the free flow of the oil and which deposit about the piston rings causing them to stick. There is also developed, as the result of oxidation, appreciable acidity in the oil which has a deleterious effect upon contacted material, particularly certain types of alloy bearing metals; and in the event the oil is being used as a. dielectric, the development of acidity obviously reduces their effectiveness in this respect. Also the lubricating effectiveness of viscous mineral oil fractions is reduced by virtue of the relatively large change in viscosity with change in temperatures of engine operation. Another shortcoming of viscous mineral oil fractions is their characteristically relatively high pour points which militate against their use at temperatures less than about 30 F.

A great many materials or mineral oil agents have been proposed for use in mineral oil fractions to counteract the aforesaid undesirable chemical and physical features thereof. For example, many compounds containing sulfur in non-corrosive form have been proposed as stabilizers for said oils. .Among these compounds are sulfurized olefins and sulfurized oils such as sulfurized corn oil, sulfurized sperm oil, etc. Sulfurized olefins, however, are somwhat undesirable in view of their ease of oxidation to acidic materials, such materials having a deleterious effect on bearing metals. Similarly, the sulfurized oils, such as sulfurized sperm oil which contains sulfurized fatty esters of mono-, diand tri-hydric alcohols, having a tendency to decompose when used in mineral oils in modern combustion engines, the decomposition products being gumlike in character and thereby causing metal parts to stick. Sulfurized compounds as have been proposed also have the undesirable property of imparting color to mineral oils with which they have been admixed in small amounts, thus limiting their usefulness to mineral oils where color is a minor consideration.

In general, the various materials, those containing sulfur and/or other characterizing elements hitherto proposed are specific in improving but one property of the oil. For example, one such Application June 12, 1943, erial No. 490,683

bility such as the oxidation characteristics of the w oil but will not improve, and may in fact impair, the viscosity characteristics or pour points of the oil. correspondingly, another additive may improve the physical characteristics as by greatly decreasing the pour point of the oil and not improve the oxidation characteristics thereof. Thus, there has been a demand for mineral oil addition agents which will improve an oil in several respects, such agents thereby earning the designation multifunctional addition agents."

The present invention is predicated upon the discovery of a novel class of multifunctional mineral oil addition agents which will improve several important properties of the oil to which it is added in small amounts. Thus the primary objective of this invention is the provision of a mineral oil composition containing such improving agents.

The novel class of multifunctionalimproving agents of thi invention are sulfurized unsatu rated ketones, and more specifically those ob tained by sulfurization, with elementary sulfur, of an unsaturated ketone having at least one olefin group C=C separated from the keto group by at least one carbon atom. The unsaturated ketones of the type described may be represented by the general Formula I:

wherein R is hydrogen or an aliphatic group containing at least one carbon atom, and preferably containing from one to ten carbon atoms: R. is an aliphatic group containing at least one carbon atom, and preferably containing from one to ten carbon atoms; and R" is an aliphatic group containing at least one carbon atom, and when containing two or more carbon atoms may be saturated or unsaturated. Typical ketones of this type are allyl acetone, diallyl acetone, dioleyl ketone, etc.

It will be apparent from general Formula I that the unsaturated ketones may be symmetrical or unsymmetrical (mixed) ketones, and that the symmetrical ketones, which are preferred herein, will be represented by the following general Formula II:

wherein R and R. are as defined above. It will be seen, therefore, that the symmetrical ketones are characterized by the linkage wherein R." is as previously defined above. Par.- ticularLv preferred of the ketones having this additive may substantially improve chemical sta- 00 structure is dioleyl ketone.

It is believed that the chemical reaction involved in the sulfurization of the aforesaid ketones may be represented by the following Equation III:

wherein R and R are as previously defined. This representation is supported by the fact that practically no hydrogen sulfide is evolved during the reaction.

While completely sulfurized ketones of the type shown in Equation III are preferred herein, those sulfurized ketones in which not all of the olefin groups are sulfurized are effective improving agents and, accordingly, are contemplated herein.

In general the sulfurized ketones of this invention are prepared by reacting a ketone of the type described above with elementary sulfur at elevated temperatures until all of the sulfur has chemically combined. It is considered that all of the sulfur has chemically combined with the ketone when the sulfurized ketone obtained therewith is non-corrosive, as indicated by only aslight tarnish or discoloration of a polished copper strip, immersed in a 1 per cent blend of the reaction product in mineral oil and heated to 150 C. for 3 hours. Although the amount of elementary sulfur used in the preparation may be varied considerably, it is preferred to use from about 5 per cent to about 15 per cent by weight of the ketone used. While elevated temperatures greater than about 150 C. may be used, the preferred temperature range is from about 175 C. to about 195 C. The preferred temperature range has been found to be particularly advantageous inasmuch as undesirable side reactions, which produce unsatisfactory by-products, are kept to a minimum. Consequently, less refining of the non-corrosive sulfurized ketone is necessary. During the reaction, it is desirable, but not necessary, to introduce a non-oxidizing or inert gas such as nitrogen into the reaction mixture; the use of an inert gas at this stage makes it possible to obtain a lighter-colored product and minimizes the formation of undesirable by-products. Sulfurired ketones so obtained may be further refined, to im-- prove their color by contact with activated clay or other decolorizing materials.

It has been found that the color of the ketone used in the reaction with sulfur greatly influences the color intensity of the sulfurized product obtained therefrom. For example, when a light, pale-yellow oleone (dioleyl ketone) is heated with sulfur for 4 hours, the brown non-corrosive viscous liquid which results imparts only a slight discoloration to a mineral oil when blended therewith in minor proportions. However, when a less refined, green oleone is sulfurized and blended as before, a considerably darker mineral oil composition is obtained. The procedure outlined above may be modified by the use of an inert diluent such as a petroleum oil during the sulfurization of the ketone. The diluent will then be removed after the reaction has proceeded to completion. It will be apparent, however, that a mineral lubricating oil may be used as the diluent and the resultant reaction mixture will be a blend or concentrate of the sulfurized ketone in mineral oil.

In order that the character of the sulfurized ketones of this invention may be better understood the following illustrative example is provided below:

Exlmru: 1

a.Reaction mixture:

200 grams of oleone (dioleyl 0r diheptadecenyl ketone) 24 grams elementary sulfur. Nitrogen gas.

b.-Procedure: Twenty-four grams of sulfur were added slowly over a k hour period to 200 grams of oleone in a reaction vessel equipped with a mechanical stirrer, upright condenser, thermometer and an inlet tube extending to within a few inches above the reaction mixture. The nitrogen gas is introduced through the inlet tube in order to maintain a non-oxidizing atmosphere. During the addition of sulfur the reaction mixture is stirred and heated from about C. to about C. The reaction is mildly exothermic, and the temperature was raised slowly up to about C. where it was held for 4 hours. The reaction was considered complete, that is, that all of the sulfur was chemically combined, when the reaction product caused only a small amount of tarnish or discoloration on a polished copper strip immersed in a 1 per cent blend of the reaction product in mineral oil and heated at 150 C. for 3 hours. The product, sulfurized oleone, is a. viscous, brown oil containing 10.5 per cent sulfur.

To demonstrate the effectiveness of sulfurized ketones of the type described above in the mineral oil compositions contemplated by this invention, we have conducted several comparative tests, the results of which are listed below with representative mineral oils alone and with the same oils blended with a typical compound, the sulfurized oleone obtained as described in Example 1.

POUR Pomr Darasssmr ACTION This series of tests was conducted with a mineral lubricating oil fraction having a Saybolt Universal viscosity (S. U. V.) of 65 seconds at 210 F. and an A. S. T. M. pour point of 20 F. The blank oil and oil blends were tested at the same time. The results of these tests are listed below in Table I.

Connosron 'Irzsr In addition to the foregoing pour test we have also made a test of an oil and oil blends containing the representative improving agent, sulfurized oleone of Example 1, to determine the comparative behavior of unblended oil and improved oil compositions toward metal bearings.

Motor oils, especially those refined by certain solvent extraction methods, tend to oxidize when submitted to high temperatures and to form products which are corrosive to metal bearings. This corrosive action may be quite severe with certain bearings such as those having the corrosive susceptibility of cadmium-silver alloys; and may cause their failure within a comparatively short time. The following test was used to determine the corrosive action of 5 the motor oil on an' automotive connecting rod.

The oil used was a solvent refined oil having a Saybolt Universal viscosity of 53 seconds at 210 1''. The oil was tested by adding a section of a bearing containing a cadmium-silver alloy surface and weighing about 6 grams and heating it to 175 C. for 22 .hours while a stream of air was bubbled against the surface of the bearing. The loss in weight of the bearing during this treatment measures the amount of corrosion that has taken place. A sample of the. oil containing an improving agent was run at the same time as a sample of the straight oil, and the loss in weight .of the bearing section in the inhibited oil can be compared directly with the loss in weight oi the section in the uninhibited oil. The results obtained in this test are tabulated in Table II below.

Table II Bearing Lossin Milligrams Per Cent oi Suliurized OleoneAdded Untreated Oil'Con- Mineral taining Bul- Lubricating iurlzed Oil Oleone 1'7 39 g, 39 o a 39 3 ACCELERATED CORROSION TEST This test is used to determine the corrosive nature of lubricating oils under simulated operating conditions. The apparatus used consists of a circulating arrangement whereby oil at 325 F., under a pressure of 10 pounds er square inch, is sprayed against a standard cadmium-nickel bearing for a period of 5 hours. The amount of oil under constant circulation in the system is 1500 cc. In passing through the system, the oil comes in contact with cast iron, steel, stainless steel, copper, and the aforesaid cadmium-nickel bearing, and is also exposed to aeration. The oil -used in this test contains a small amount of an accelerator, namely, iron naphthenate (commercially designated as Nuodex, 6 per cent Fezoa) which greatly increases the rate of oxidation of the oil. The degree of oxidation suffered by the oil is shown by the development of acidity therein as measured by the neutralization number (N. N.), the loss in weight in grams of the cadmium-nickel bearing and the percentage of viscosity increase.

The specific base oil used in this test was a solvent refined oil having a Saybolt Universal viscosity of 65 seconds at 210 F. and containing 0.17 per cent of Nuodex; and the oil blends contained small amounts of the aforesaid suliurized oleone in this base oil, The results of these tests We have also carried out tests of an oil and an oil blend containingv a representative improving agent of the type contemplated herein. namely, sulfurized oleone, to determine the comparative behavior of the unblended oil and the 1111- proved oil compositions under actual operating conditions.

In this test a single-cylinder Lauson engine was operated for 38 hours at an oil temperature of 290 F. and a Jacket temperature of 212 F. The, oil used was a solvent-refined oil having a Saybolt Universal viscosity of 45 seconds at 210 F., and the oil blend used was a blend of said oil and said sulfurized oleone. After 36 hours the acidity, neutralization number and the kinematic viscosity of the oil were measured. The results are shown in Table IV below.

The sulfurized ketones of the type described by the general formula shown above may be used in mineral oil fractions in various amounts, depending upon the character of the oil,- the degree of improvement oi. the oil to be obtained, the conditions under which it is to be used, etc. In general, however, it appears that the desired improvement of the oil may 'be eflected with these sulfurized ketones in amounts up to about 5 per cent. Substantial improvement is efl'ected, however, with amounts from about 0.25 per cent to about 2 per cent.

It is to be understood that while we have described hereinabove certain typical procedures for making the oil addition agents of this invention and have referred to certain reaction products and mineral-oils, the invention is not limited to these specific features of the description but includes variations of the procedures whichwill be apparent to those skilled in the art and other typical sulfurized ketones and petroleum products coming within the scope of the apcorrosive, sulfurized aliphatic ketone obtained by sulfurizing an unsaturated aliphatic ketone with elementary sulfur at an elevated temperature, said ketone having at least one olefin group separated from the keto group by at least one carbon atom.

2. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, sufficient to stabilize said oil fraction, of a noncorrosive, sulfurized aliphatic ketone obtained by sulfurizing an unsaturated aliphatic ketone with elementary sulfur at a temperature above about C., said ketone having at least one olefin group separated from the keto group by at least one carbon atom.

3. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, sumcient to stabilize'said oil fraction, of a non-corrosive, sulfurized aliphatic keton'e obtained by sulfurizing an unsaturated aliphatic ketone with elementary sulfur at atemperature between about C. and about C.,.said ketone having at least one olefin group separated from the keto group by at least one carbon atom.

4. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, sufficient to stabilize said 011 fraction, of a non-corrosive, sulfurized aliphatic ketone obtained by sulfurizlng an unsaturated aliphatic ketone with from about per cent to about 15 per cent by weight of elementary sulfur at a temperature above about 150 0., said ketone having at least one olefin group separated from the keto group by at least one carbon atom.

5. An improved mineral oil composition com. prising a viscous mineral oil fraction having in admixture therewith a minor proportion, sufiicient to stabilize said oil fraction, of a non-corrosive, sulfurized aliphatic ketone obtained by sulfurizing an unsaturated aliphatic ketone with elementary sulfur at a temperature above about 150 C. in the presence of an inert gas, said ketone having at least one olefin group separated from the keto group by at least one carbon atom.

6. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, suflicient to stabilize said oil fraction, of a non-corrosive, suifurized aliphatic ketone obtained by sulfurizing an unsaturated aliphatic ketone with elementary sulfur at a temperature above about 150 C., said ketone having the general formula RC=CR'-C--R" wherein R is selected from the group consisting of hydrogen and an aliphatic group containing at least one carbon atom; and R and R" are allphatic groups containing at least one carbon atom. I

'7. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, sufficient to stabilize said oil fraction, of a non-corrosive, sulfurized aliphatic ketone obtained by sulfurizing an unsaturated aliphatic ketone with from about 5 per cent to about 15 per cent by weight of elementary sulfur at a temperature above about 150 0., said ketone having the general formula wherein R is selected from the group consisting.

wherein R is selected from the group consisting of hydrogen and an aliphatic group containing at least one carbon atom; and R is an aliphatic group containing at least one carbon atom.

9. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, sufilcient to stabilize said oil fraction, of a non-corrosive, sulfurized aliphatic ketone obtainedby sulfurizing an unsaturated aliphatic ketone with from about 5 per cent to about 15 per cent by weight of elementary sulfur at a temperature above about C., said ketone having the general formula wherein R is selected from the group consisting of hydrogen and an aliphatic group containing at least one carbon atom; and R is an aliphatic group containing at least one carbon atom.

10. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, sumcient to stabilize said oil fraction, of a non-corrosive, sulfurized aliphatic ketone obtained by sulfurizdng an unsaturated aliphatic ketone with elementary sulfur at a temperature above about 150 0., said ketone having the general formula wherein R is selected from the group consisting of hydrogen and an aliphatic group containing at least one carbon atom; and R is an aliphatic group containing from one to ten carbon atoms.

11. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, sufficient to stabilize said oil fraction, of non-corrosive, sulfurized oleone obtained by sulfurizing dioleyl ketone with elementary sulfur at a temperature above about 150 C.

12. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, sufllcient to stabilize said oil fraction, of non-corrosive, sulfurized oleone obtained by sulfurizing dioleyl ketone with from about 5 per cent to about 15 per cent of elementary sulfur at a temperature between about C. and about C.

13. A non-corrosive, mineral oil concentrate containing a minor proportion of a non-corrosive, sulfurized aliphatic ketone, said concentrate being obtained by sulfurizing an unsaturated aliphatic ketone with elementary sulfur at an elevated temperature in .the presence of a mineral oil fraction, and said ketone having at least one olefin group separated from the keto group by at least one carbon atom.

14. A non-corrosive, mineral oil concentrate containing a minor proportion of a. non-corrosive sulfurized aliphatic ketone. said concentrate being obtained by sulfurizing an unsaturated allphatic ketone with from about 5 per cent to about 15 per cent of elementary sulfur at a temperature above about 150 C. in the presence of a mineral oil fraction, and said ketone having the general formula wherein R is selected from the group consisting of hydrogen and an aliphatic group containing at least one carbon atom; R and R" are aliphatic groups containing at least one carbon atom.

15. A non-corrosive, mineral oil concentrate mineral oil fraction, and said ketone having the general formula wherein R is selected from the group consisting of hydrogen and an aliphatic group containing at least one carbon atom; and R is an aliphatic group containing from one to ten carbon atoms.

16. A non-corrosive, mineral oil concentrate containing a minor proportion of non-corrosive, sulfurized oleone, said concentrate being obtained by sulfurizing dioleyl ketone with from about per cent to about 15 per cent of elementary sulfur at a temperature between about 175 C. and about 195? C. in the presence of a viscous mineral oil fraction.

17. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, from about 0.25 per cent to about 5 per cent of a noncorrosive, sulfurized aliphatic ketone obtained by sulfurizing an unsaturated aliphatic ketone with elementary sulfur at an elevated temperature, said ketone having at least one olefin group separated from the ketone group by at least one carbon atom.

18. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, from about 0.25 per cent to about 5 per cent, of a noncorrosive, sulfurized ketone obtained by sulfurizing an unsaturated aliphatic ketone with elementary sulfur at a temperature above about 0., said ketone having the general formula wherein R is selected from the group consisting of hydrogen and an aliphatic group containing at least one carbon atom; and R and R" are aliphatic groups containing at least one carbon atom.

19. An improved mineral oil composition comprising a viscous mineral oil fraction having in admixture therewith a minor proportion, from about 0.25 per cent to about 5.0 per cent of noncorrosive, sulfurized oleone obtained by sulfurizing dioleyl ketone with from about 5 per cent to about 15 per cent of elementary sulfur at a temperature between about C. and about C.

FERDINAND P. O'I'I'O. RONALD E. MEYER.

REFERENCES CITED The following references are of record in. the 

